Synthesis of Al-substituted 11 A tobermorite from newsprint recycling residue: a feasibility study
Newsprint recycling is responsible for significant volumes of secondary waste material for which further reprocessing and market development would be beneficial. In response to this problem, a layer lattice, ion exchange material, Al-substituted 11 A tobermorite, has been synthesised from newsprint recycling residue comprising gehlenite (Ca{sub 2}Al{sub 2}SiO{sub 7}), akermanite (Ca{sub 2}MgSi{sub 2}O{sub 7}), {beta}-dicalcium silicate (Ca{sub 2}SiO{sub 4}) and anorthite (CaAl{sub 2}Si{sub 2}O{sub 8}) under hydrothermal conditions at 100 deg. C in the presence of NaOH. The hydrogarnet phase, katoite (Ca{sub 3}Al{sub 2}SiO{sub 12}H{sub 8}), was also formed. Similar treatment regimes in the presence of LiOH and KOH did not yield significant quantities of Al-substituted 11 A tobermorite. A batch sorption study confirmed that the Al-substituted 11 A tobermorite-bearing product was effective in the exclusion of Cd{sup 2+}, Pb{sup 2+} and Zn{sup 2+} from acidified aqueous media. The potential to enhance the yield of Al-substituted 11 A tobermorite relative to that of katoite and thus optimise the ion exchange efficiency of the product is discussed with respect to its application to heavy metal-contaminated wastewater treatment.
- OSTI ID:
- 20884647
- Journal Information:
- Materials Research Bulletin, Vol. 38, Issue 3; Other Information: DOI: 10.1016/S0025-5408(02)01056-5; PII: S0025540802010565; Copyright (c) 2002 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
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